In Orthogonal Frequency Division Multiple Access (OFDMA) broadband wireless systems resource blocks may consist of groups of sub-carriers, sub-channels or chunks in frequency. Symbols or groups of symbols may be referred to as slots or sub-frames in time. OFDMA systems may assign a unique sub-channel to a single user. Sub-channel assignments and modification of these assignments, including adding and removing users, are typically performed by a sequential algorithm that may be highly complex or take a long time to implement.
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